Which is true about regression testing?

Regression testing is a crucial practice in software testing that ensures that new code changes do not adversely affect existing functionality. It is commonly associated with various testing phases, including integration testing. During integration testing, changes made to individual modules are combined and tested as a group. As new features or bug fixes are added, regression tests help verify that these changes integrate well with the existing system without introducing new defects.

Option B highlights the fact that regression tests are indeed performed during integration testing, serving the purpose of checking the interactions between integrated components after changes have been made. This is important because integration testing not only verifies that new functionality works as intended but also checks that previously working features remain operational.

Understanding the role of regression tests within integration testing is essential for maintaining the integrity of the software throughout its development lifecycle, as it helps to catch any potential issues early in the development process.